Answer:
Michael is running for president. The proportion of voters who favor him is 0.3. A simple random sample of 100 voters is taken.
a)
What is the expected value :: n*p = 100*0.8 = 80
standard deviation:: sqrt(n*p*q) = sqrt(80*0.2) = 16
where q is proportion of voters who do not favor Michael. (q=0.2)
and shape of the sampling distribution is binomial distribution which is approximately a bell shaped.
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what is the probability that the number of voters in the sample who will not favor Michael will be more than 16
P(X < 16.0) = P((x - 20) / 4.0) < (16.0 - 20) / 4.0) = P(Z < -1.00) = .1587
P(X > 16.0) = 1 - 0.1587 = 0.8413
